Automatic contact mechanism for electric revolution-indicators.



F. W. WOOD. AUTOMATIC CONTACT MECHANISM FOR ELEUTRIO REVOLUTION INDICATORS.

APPLICATION FILED MAR. 20, 1907.

Patented Sept. 15, 1908.

2 SHEETS-SHEET 1.

P. W. WOOD. AUTOMATIC CONTACT MECHANISM FOR ELECTRIC REVOLUTION INDICATORS.

APPLICATION FILED MAR. 20. 1907.

Patented Sept. 15,1908

2 SHEETSSHEET 2.

mm: c

UNITED STATES PATENT OFFICE.

FRANK'W. WOOD, OF NEWPORT NEWS, VIRGINIA, ASSIGNOR TO CHARLES CORY AND JOHN M.

' CORY. OF NEW.YORK, N. Y.

Specification of Letters Patent.

Patented Sept. 15, 1908.

Application filed March 20, 1907. SeriaI'No. 363,361.

Toallf'whom it may concern;

'Be it known that I, FRANK W. WOOD, a citizen oftli-e United States, residing at Newgort News, in the county of'VVar'wick and tate of Virginia, have invented new and useful Improvements in Automatic Contact Mechanism for Electric Revblution-Indicaism of thischaracter designed for continuous operation by a'shaft, the speed, direction, or number of revolutions of which it is desirable to indicate or register.

My invention is particularly designed for use on shi board, in connection with the propeller s aft, and to this end Ihave provided certain details of construction not necessary, perhaps, where my inventionis em loyed elsewhere, but it is, of course, to be im erstood, that the invention may be used ,Wlt-h e ual advantage in connection with any other s aft or. rotating part on any machine 7 whatever. l

The primary object of my invention is to provide automatically operating contact mechanism which shall serve to close periodically one of twov circuits according to the direction of rotation of the shaft, 'and which cir cuits, when so closed, shall serve'to o erate any suitable indicating or registerin evice, located at any desired distance from t e shaft; 1 A further ob'ect is to provide mechanism 'of the above 0 ara'cter which shall be practically water and dust proof, simple and in'section. Fi 2 is a sectional plan view of the brush ho ders, and bracket therefor. Fig. 3 is a sectional elevation, taken on the line 3-3 of Fig. 1, looking in the direction of the arrow. Fig. 4 is a fragmentary plan view of the worm. Fig. 5 is an elevation of the worm wheel, showing the worm in engage menttherewith- 6 .is a development of tors ofl-which the following is a specification. invention relates to rotary contact 10 mfec anism, and more especially to mechanthe contact drum or commutatonzhereinafter described.

Referring to the drawin s in detail, the numeral 1 denotes the sha t from which the mechanism is driven. Clairrped upon the shaft 1 is a worm 2, of two or three convolutions, 3, in the form of a ring, split as at 5, and clam ed to the shaft by meansof bolts 6, passing t rough lugs 4.,

Arranged to gear with the wormis the worm wheel 7, carried on the end of a shaft 8, which passes through 'a bearing 9 into the casing 14, containing-the contact mechanism. Screwed over the bearing 9 is a land 10, which forms a tight joint aroun the shaft 1. An oil cu cover is mounted in t e bearing 9 for supplyin oil thereto. Just inside the journa 9, a co lar 12, having a radial flange, is secured to the shaft 8 by'means of set screws 13-.

' The casing 14, which preferably consists of case metal, is provided with erforated lugs 15, by means of which the casing is attached to a suitable support The casing is provided with a cover 16, held by means of screws 18, ti htly against packing 17, laid in the edge of t e casing, soas to form a water and dust-proof seal.

The other end of the shaft 8 is reduced to form a journal 20 which turns in the bearing 19. This bearing also carries an oil cu 21, provided with a-cover attached to a c ain 71. This cover is preferably provided with s ring clips 72, which take over shoulders on the cup, and hold the cover in position. Adjacent the bearing 19, a collar 22, having a radial flange, is secured to the journal 20 by means of set screws 23.

Mounted on theshaft 8 is the contact drum or commutator. This comprises a central hub or spider, 24, provided with an internally projecting square thread, 25, meshing with a similar spiral groove 26 formed in said shaft.

This spider supports a cylindrical body 27, of

insulating material, such as fiber or hard rubber, carrying on its surface stri s 28, 29, 30, 31 and 33 of copper or brass. he strips 28 are located, one near each end of the drum, and consists of continuous metal bands or hoops. seen in Fig. 6. The strips 29 and 30 are also circumferentially arranged, but consist of 11, provided with a The development of this drum is two separated sections, as shown, and be tween theends'of the sections are located the transverse strips 31 and 33 each of a length about equal to the combined width of the means of screws 34, and the strips 31 etc. are secured to the body by means of screws 32,

all as clearly shownin Fig. 1.

"Disposed immediately above the drum,-

and in a perpendicular plane passing through its axis, 1s a set of contact brushes 35, 36, 37. These'bl'ushes *maypand preferably do, consist of carbon rods,.hav1ng rounded lower ends. They are pressed into engagement with their respectlve. contact strips on the drum by means' of springs, 38, 39, 40, arranged above the same. Each brush and'its associated spring is contained in an individual.

case, 41, 42, 43, all of which cases are secured toa supporting bracket 45, by means of screws 44. Suitable insulation, 46, 47 is interposed in such a way as to-effectually insulate each brush from the others. The bracket 45 is adapted tofbe secured to the casing 14, as by screws 51. Secured on each of thecases 41, 42, 43, :as by screws 53, are copper terminals .48, 49, 50, to th'e end of which, wires 61, 62, 63 may be attached, as by soldering. These wires or leads are adapted to extend out through the conduit 52, to any point where it is desirable tolocate the indicator.

At the rear end, the hubof the drum is ex tended forming the rojectin sleeve 54 (see Fig. 1), and carried by said sleeve and preferably formed integral therewith are two cam projections or ratchet teeth," 55, 56.

These teeth are offset, as shown in Fig. 1, so

as to lie in difierent (planes, are formed with one end beveled, an a square shoulder.

Referring to Fig. 3, it will be seen that the other end forming these .square shoulders are approximately 45 180 apart, and that the beve 1n opposite directions.

ed ends face A pawl 57 having a depending square end 58, adapted to ride on sald sleeve, is pivoted at 59 to a bracket 60, secured to the casing.

mechanism'is as follows: Asthe shaft 1 rotates, 1t drives the worm wheel 7, and shaft 8, thus rotating drum 27. The strips 28 have noelectrical'function, but act merely as wear plates for supportin the brushes.

Also, the strips 29 and 30 are insulated from each other, and serve to insulate the brushes wlule 1n contact with them. 'VVhen, however, any two brushes, are bridged by oneof 4 the plates 31,33, the circuit is closed between them. As shown, only two strips, 31, and 33, are provided, and with this arrangement, assuming at ten to one worm gear, it is evident that a circuit between the brushes brush 35 remains idle.

' will be closed once for every five revolutions ofthe shaft 1. It may often be desirable, however, to close-the circuit more frequently than every fifthrevolution. So, for example, if five contact strips 31 are provided, and equally spaced around the drum, it is evident that the circuit would be closed by one of them passing the brushes every second revolution of the shaft 1. It will therefore be understood, that by varying the number of indication may be' obtained.

' In the position of the parts shown in Fig. 1, andassuming the shaft 8 as viewed from the front, to be turni in a counter-clockwise direction, the-circuit will be eriodically closed between brushes .36 an 37, while As the shaft 8 rotates in this direction the end of sleeve 54 is held jammed against collar 22, and the pawl of strips such as 31, any desired frequency- 57 rides up the beveled face of tooth 55 anddrops behind the shoulder of the same at each revolution, the pawl'57, and.tooth 55, being, in'this position, in the same plane.- Sup ose now the direction of rotation of the sha tto be reversed. Before the sleeve 54 can make a complete revolution, the square shoulder of tooth 55 will catch against the square end of the pawl, thus temporarily locking the sleeve andd'rum against rotation, But the shaft 8 revolving, causes the screw thread 25, 26, to draw the drumand sleeve longitudinally along the'shaft, until the end.

of the drum jams against collar 12. This movement carries the tooth 55 clear of the pawl 57, and the drum immediately begins to revolve. The pawl isnow in .the'plane of tooth 56, and rides over it in the same manner as it'didover tooth 55, the direction of rotation now being reversed. It will thus be observed that the checking ofthe drum is only momentary, and thatit is automatically shifted, by means of the pawl, u on its rotation being reversed. In the shi 'tedoosition of'the drum, the brush 37 becomesi le, and the circuit is periodically closed between brushes 35. and 36. Brush 36 constitutes a common terminal,- andis always included in either of the two circuits,'the otherterminal The operation of my improved contact.

often'it isclosed, so as to give readings of both speed and direction of the shaft 1. If the direction of rotation is reversed again,

the shoulder of tooth 56 will engage pawl 57 as clearly shown in Fig. 3, thus causing the drum to shift back to its original position. What I claim is: f 1. In a device of the class described, a

rotating member, terminals of a plurality of circuits arranged to bear against said member, and means controlled by the direction of rotation of said member for shifting the same into position for selecting and closing periodically one of said circuits. 2. In an electrical .contact mechanism, a plurality of brushes, which said brushes bear,-and means carried by said member for .bri'dging, periodica ly, onepair ofbrushes onl when rotating in one direction, and means or. shifting said member into position to e another pair of brushes when rotating int c other direction. 3. In a' -dev'ice-ofthe class described, a rotating member, capable of occupying a plurality of positions longitudinally of its shaft, a plurality" of electrical circuits, and means controlled by said-second member for closing one of another of said circuits, according to its position on its shaft.

v4. In a device of the class described, a rotating member, -a second rotating member I driven thereby, and mounted on a shaft, so

as to be capable of longitudinal movement thereon, and means controlled by changes in the direction of rotation of said first member, for shifting said second member to different positions onits shaft.

' 5. In combination, a rotating shaft, a member mounted for longitudinal move ment thereon, terminals for a plurality of circuits any of' which is adapted to be periodically closed by said member while said shaft rotates continuously in one direction,

and means for automatically shifting saidmember into operative relation with a different pair of terminals for eachchange in the direction of rotation of said shaft.

'6. In combination, a rotating shaft, a

member mounted thereon to normally rotate therewith, and means for automatically shifting said member longitudinally of said" shaft, whenever its movement is momentarily checked. 7

7. In combination, a rotating shaft, a member mounted thereon to normally rotate therewith, automatic means for momentarily locking the member against rotation when its direction of rotationv changes, and means between said member and shaft for causing the former to shift, longitudinally, upon being so locked.

8. In combination, a rotating shaft, a member mounted thereon to normally rotate therewith, a cam tooth carried by said member, a pivoted pawl adapted to cooperate therewithto momentarily lock the member when its direction of rotation changes, and automatic means, thrown such looking, to so shift said member as to free said tooth from said pawl.

9. In combination, a shaft having a spiral groovecut therein, a member mounted on a rotating member on I into operation by meshing with said groove, said shaft and member normally rotating together, and means for arresting the motion of said mem her, and thereby causing the thread to shift the same, whenever its direction of rotation changes.

10. In a device of the class described, a rotating drum carrying contact strips, brushes cooperatin therewith and forming terminalsfor a plura ity of, circuits, and means for antomaticallyshifting said drum so as to close one or'another of said circuits, in accordance with its-direction of rotation.

11. In a device of the class described,-a rotating drum, brushes, forming theterminals of a plurality of circuits yie dingly held in contact therewith, means for continuously rotating said drum and means controlled by the direction of rotation of said drum for selecting and periodically closing one of said circuits.

12. In a device of the class described, a casing, a shaft journaled therein, collars fixed to the shaft, a drum'mounted on the shaft be tween the collars, to turn continuously therewith, and capable of longitudinal movement on the shaft, and terminals of a plurality of circuits arranged adjacent said drum, and adapted to be controlled thereby.

13. In a device of the class described, a casing, a shaft journaled therein, collars fixed to the-shaft, a drum mounted on the shaft between the collars, to turn continuously there with, automatic means for forcing the drum into engagement with one or the other of the collars, according to the direction of rotation of said shaft, and circuit terminals arranged adjacent said drum and controlled thereby.

14. In a device of the class described, three contact brushes forming the terminals of a pair of circuits, a rotary contact drum arranged to cooperate therewith and carrying a plurality of equally spaced contact strips, the inner ones. of which are sectional and the outer ones of which are each continuous bands, and means for reducing a relative lateral displacement etween said drum and brushes,

said shaft and having an internal thread whereby said sectional contact strips are.

caused to select and periodically bridge two of said three brushes, and said continuous bands serve as wear plates for the third brush which is not active.

15. In a device of the class described, a rotatable drum, means for driving. the same, means overned by the direction of rotation of the drum for shifting the'same endwise, a

plurality of equally spaced insulated contact strips carried by said drum, and brushes, forming the terminals of a plurality of circuits, arranged to ride on said strips, one of said strips being always idle, and serving to support a brush when the same is not in circurt.

16. In a device of the class described, a plu- In testimony whereof I have hereunto set rali-tyof brushes equally spaced, a rotating my hand in presence of two subscribing Wit contact drum carrying a plurality of equally nesses.

spaced transverse contact strips of a length v FRANK W; WOOD. 5 to bridge two of said brushes, and means for Witnesses:

shiftingsaid drum, to bring said stri s into E.- W. HOUSE,

position to bridge any two of said brus es. M. S. GoDWIN. 

